1464 lines
32 KiB
C++
1464 lines
32 KiB
C++
/* Copyright (C) 2001-2017 Peter Selinger.
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* This file is part of Potrace. It is free software and it is covered
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* by the GNU General Public License. See the file COPYING for details. */
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/* Routines for manipulating greymaps, including reading pgm files. We
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* only deal with greymaps of depth 8 bits. */
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include <errno.h>
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#include <math.h>
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#include <stddef.h>
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#include <stdlib.h>
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#include <string.h>
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#include "bitops.h"
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#include "greymap.h"
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#define INTBITS ( 8 * sizeof( int ) )
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#define mod( a, n ) \
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( ( a ) >= ( n ) ? ( a ) % ( n ) : ( a ) >= 0 ? ( a ) : (n) - 1 - ( -1 - ( a ) ) % ( n ) )
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static int gm_readbody_pnm( FILE* f, greymap_t** gmp, int magic );
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static int gm_readbody_bmp( FILE* f, greymap_t** gmp );
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#define TRY( x ) \
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if( x ) \
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goto try_error
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#define TRY_EOF( x ) \
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if( x ) \
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goto eof
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#define TRY_STD( x ) \
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if( x ) \
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goto std_error
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/* ---------------------------------------------------------------------- */
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/* basic greymap routines */
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/* calculate the size, in bytes, required for the data area of a
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* greymap of the given dy and h. Assume h >= 0. Return -1 if the size
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* does not fit into the ptrdiff_t type. */
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static inline ptrdiff_t getsize( int dy, int h )
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{
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ptrdiff_t size;
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if( dy < 0 )
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{
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dy = -dy;
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}
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size = (ptrdiff_t) dy * (ptrdiff_t) h * (ptrdiff_t) sizeof( gm_sample_t );
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/* check for overflow error */
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if( size < 0 || ( h != 0 && dy != 0 && size / h / dy != sizeof( gm_sample_t ) ) )
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{
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return -1;
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}
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return size;
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}
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/* return the size, in bytes, of the data area of the greymap. Return
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* -1 if the size does not fit into the ptrdiff_t type; however, this
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* cannot happen if the bitmap is well-formed, i.e., if created with
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* gm_new or gm_dup. */
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static inline ptrdiff_t gm_size( const greymap_t* gm )
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{
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return getsize( gm->dy, gm->h );
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}
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/* return new greymap initialized to 0. NULL with errno on error.
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* Assumes w, h >= 0. */
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greymap_t* gm_new( int w, int h )
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{
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greymap_t* gm;
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int dy = w;
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ptrdiff_t size;
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size = getsize( dy, h );
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if( size < 0 )
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{
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errno = ENOMEM;
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return NULL;
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}
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if( size == 0 )
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{
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size = 1; /* make surecmalloc() doesn't return NULL */
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}
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gm = (greymap_t*) malloc( sizeof( greymap_t ) );
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if( !gm )
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{
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return NULL;
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}
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gm->w = w;
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gm->h = h;
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gm->dy = dy;
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gm->base = (gm_sample_t*) calloc( 1, size );
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if( !gm->base )
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{
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free( gm );
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return NULL;
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}
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gm->map = gm->base;
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return gm;
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}
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/* free the given greymap */
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void gm_free( greymap_t* gm )
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{
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if( gm )
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{
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free( gm->base );
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}
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free( gm );
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}
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/* duplicate the given greymap. Return NULL on error with errno set. */
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greymap_t* gm_dup( greymap_t* gm )
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{
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greymap_t* gm1 = gm_new( gm->w, gm->h );
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int y;
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if( !gm1 )
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{
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return NULL;
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}
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for( y = 0; y < gm->h; y++ )
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{
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memcpy( gm_scanline( gm1, y ), gm_scanline( gm, y ),
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(size_t) gm1->dy * sizeof( gm_sample_t ) );
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}
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return gm1;
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}
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/* clear the given greymap to color b. */
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void gm_clear( greymap_t* gm, int b )
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{
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ptrdiff_t size = gm_size( gm );
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int x, y;
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if( b == 0 )
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{
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memset( gm->base, 0, size );
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}
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else
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{
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for( y = 0; y < gm->h; y++ )
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{
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for( x = 0; x < gm->w; x++ )
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{
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GM_UPUT( gm, x, y, b );
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}
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}
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}
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}
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/* turn the given greymap upside down. This does not move the pixel
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* data or change the base address. */
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static inline void gm_flip( greymap_t* gm )
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{
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int dy = gm->dy;
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if( gm->h == 0 || gm->h == 1 )
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{
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return;
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}
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gm->map = gm_scanline( gm, gm->h - 1 );
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gm->dy = -dy;
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}
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/* resize the greymap to the given new height. The pixel data remains
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* bottom-aligned (truncated at the top) when dy >= 0 and top-aligned
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* (truncated at the bottom) when dy < 0. Return 0 on success, or 1 on
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* error with errno set. If the new height is <= the old one, no error
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* should occur. If the new height is larger, the additional pixel
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* data is *not* initialized. */
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static inline int gm_resize( greymap_t* gm, int h )
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{
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int dy = gm->dy;
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ptrdiff_t newsize;
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gm_sample_t* newbase;
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if( dy < 0 )
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{
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gm_flip( gm );
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}
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newsize = getsize( dy, h );
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if( newsize < 0 )
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{
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errno = ENOMEM;
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goto error;
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}
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if( newsize == 0 )
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{
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newsize = 1; /* make sure realloc() doesn't return NULL */
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}
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newbase = (gm_sample_t*) realloc( gm->base, newsize );
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if( newbase == NULL )
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{
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goto error;
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}
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gm->base = newbase;
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gm->map = newbase;
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gm->h = h;
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if( dy < 0 )
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{
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gm_flip( gm );
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}
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return 0;
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error:
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if( dy < 0 )
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{
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gm_flip( gm );
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}
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return 1;
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}
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/* ---------------------------------------------------------------------- */
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/* routines for reading pnm streams */
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/* read next character after whitespace and comments. Return EOF on
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* end of file or error. */
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static int fgetc_ws( FILE* f )
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{
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int c;
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while( 1 )
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{
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c = fgetc( f );
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if( c == '#' )
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{
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while( 1 )
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{
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c = fgetc( f );
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if( c == '\n' || c == EOF )
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{
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break;
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}
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}
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}
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/* space, tab, line feed, carriage return, form-feed */
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if( c != ' ' && c != '\t' && c != '\r' && c != '\n' && c != 12 )
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{
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return c;
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}
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}
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}
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/* skip whitespace and comments, then read a non-negative decimal
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* number from a stream. Return -1 on EOF. Tolerate other errors (skip
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* bad characters). Do not the read any characters following the
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* number (put next character back into the stream) */
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static int readnum( FILE* f )
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{
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int c;
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int acc;
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/* skip whitespace and comments */
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while( 1 )
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{
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c = fgetc_ws( f );
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if( c == EOF )
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{
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return -1;
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}
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if( c >= '0' && c <= '9' )
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{
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break;
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}
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}
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/* first digit is already in c */
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acc = c - '0';
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while( 1 )
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{
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c = fgetc( f );
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if( c == EOF )
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{
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break;
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}
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if( c < '0' || c > '9' )
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{
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ungetc( c, f );
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break;
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}
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acc *= 10;
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acc += c - '0';
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}
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return acc;
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}
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/* similar to readnum, but read only a single 0 or 1, and do not read
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* any characters after it. */
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static int readbit( FILE* f )
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{
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int c;
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/* skip whitespace and comments */
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while( 1 )
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{
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c = fgetc_ws( f );
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if( c == EOF )
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{
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return -1;
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}
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if( c >= '0' && c <= '1' )
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{
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break;
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}
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}
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return c - '0';
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}
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/* ---------------------------------------------------------------------- */
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/* read a PNM stream: P1-P6 format (see pnm(5)), or a BMP stream, and
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* convert the output to a greymap. Return greymap in *gmp. Return 0
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* on success, -1 on error with errno set, -2 on bad file format (with
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* error message in gm_read_error), and 1 on premature end of file, -3
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* on empty file (including files with only whitespace and comments),
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* -4 if wrong magic number. If the return value is >=0, *gmp is
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* valid. */
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const char* gm_read_error = NULL;
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int gm_read( FILE* f, greymap_t** gmp )
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{
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int magic[2];
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/* read magic number. We ignore whitespace and comments before the
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* magic, for the benefit of concatenated files in P1-P3 format.
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* Multiple P1-P3 images in a single file are not formally allowed
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* by the PNM standard, but there is no harm in being lenient. */
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magic[0] = fgetc_ws( f );
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if( magic[0] == EOF )
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{
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/* files which contain only comments and whitespace count as "empty" */
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return -3;
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}
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magic[1] = fgetc( f );
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if( magic[0] == 'P' && magic[1] >= '1' && magic[1] <= '6' )
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{
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return gm_readbody_pnm( f, gmp, magic[1] );
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}
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if( magic[0] == 'B' && magic[1] == 'M' )
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{
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return gm_readbody_bmp( f, gmp );
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}
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return -4;
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}
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/* ---------------------------------------------------------------------- */
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/* read PNM format */
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/* read PNM stream after magic number. Return values as for gm_read */
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static int gm_readbody_pnm( FILE* f, greymap_t** gmp, int magic )
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{
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greymap_t* gm;
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int x, y, i, j, b, b1, sum;
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int bpr; /* bytes per row (as opposed to 4*gm->c) */
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int w, h, max;
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int realheight; /* in case of incomplete file, keeps track of how
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* many scan lines actually contain data */
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gm = NULL;
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w = readnum( f );
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if( w < 0 )
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{
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goto format_error;
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}
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h = readnum( f );
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if( h < 0 )
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{
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goto format_error;
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}
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/* allocate greymap */
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gm = gm_new( w, h );
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if( !gm )
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{
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goto std_error;
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}
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realheight = 0;
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switch( magic )
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{
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default:
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/* not reached */
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goto format_error;
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case '1':
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/* read P1 format: PBM ascii */
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for( y = 0; y < h; y++ )
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{
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realheight = y + 1;
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for( x = 0; x < w; x++ )
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{
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b = readbit( f );
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if( b < 0 )
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{
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goto eof;
|
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}
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GM_UPUT( gm, x, y, b ? 0 : 255 );
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}
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}
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break;
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case '2':
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/* read P2 format: PGM ascii */
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max = readnum( f );
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if( max < 1 )
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{
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goto format_error;
|
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}
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for( y = 0; y < h; y++ )
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{
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realheight = y + 1;
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|
|
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for( x = 0; x < w; x++ )
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{
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b = readnum( f );
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|
|
|
if( b < 0 )
|
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{
|
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goto eof;
|
|
}
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|
|
|
GM_UPUT( gm, x, y, b * 255 / max );
|
|
}
|
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}
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break;
|
|
|
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case '3':
|
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/* read P3 format: PPM ascii */
|
|
|
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max = readnum( f );
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|
|
|
if( max < 1 )
|
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{
|
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goto format_error;
|
|
}
|
|
|
|
for( y = 0; y < h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
|
|
for( x = 0; x < w; x++ )
|
|
{
|
|
sum = 0;
|
|
|
|
for( i = 0; i < 3; i++ )
|
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{
|
|
b = readnum( f );
|
|
|
|
if( b < 0 )
|
|
{
|
|
goto eof;
|
|
}
|
|
|
|
sum += b;
|
|
}
|
|
|
|
GM_UPUT( gm, x, y, sum * ( 255 / 3 ) / max );
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case '4':
|
|
/* read P4 format: PBM raw */
|
|
|
|
b = fgetc( f ); /* read single white-space character after height */
|
|
|
|
if( b == EOF )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
bpr = ( w + 7 ) / 8;
|
|
|
|
for( y = 0; y < h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
|
|
for( i = 0; i < bpr; i++ )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
{
|
|
goto eof;
|
|
}
|
|
|
|
for( j = 0; j < 8; j++ )
|
|
{
|
|
GM_PUT( gm, i * 8 + j, y, b & ( 0x80 >> j ) ? 0 : 255 );
|
|
}
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case '5':
|
|
/* read P5 format: PGM raw */
|
|
|
|
max = readnum( f );
|
|
|
|
if( max < 1 )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
b = fgetc( f ); /* read single white-space character after max */
|
|
|
|
if( b == EOF )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
for( y = 0; y < h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
|
|
for( x = 0; x < w; x++ )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
goto eof;
|
|
|
|
if( max >= 256 )
|
|
{
|
|
b <<= 8;
|
|
b1 = fgetc( f );
|
|
|
|
if( b1 == EOF )
|
|
goto eof;
|
|
|
|
b |= b1;
|
|
}
|
|
|
|
GM_UPUT( gm, x, y, b * 255 / max );
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case '6':
|
|
/* read P6 format: PPM raw */
|
|
|
|
max = readnum( f );
|
|
|
|
if( max < 1 )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
b = fgetc( f ); /* read single white-space character after max */
|
|
|
|
if( b == EOF )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
for( y = 0; y < h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
|
|
for( x = 0; x < w; x++ )
|
|
{
|
|
sum = 0;
|
|
|
|
for( i = 0; i < 3; i++ )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
{
|
|
goto eof;
|
|
}
|
|
|
|
if( max >= 256 )
|
|
{
|
|
b <<= 8;
|
|
b1 = fgetc( f );
|
|
|
|
if( b1 == EOF )
|
|
goto eof;
|
|
|
|
b |= b1;
|
|
}
|
|
|
|
sum += b;
|
|
}
|
|
|
|
GM_UPUT( gm, x, y, sum * ( 255 / 3 ) / max );
|
|
}
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
gm_flip( gm );
|
|
*gmp = gm;
|
|
return 0;
|
|
|
|
eof:
|
|
TRY_STD( gm_resize( gm, realheight ) );
|
|
gm_flip( gm );
|
|
*gmp = gm;
|
|
return 1;
|
|
|
|
format_error:
|
|
gm_free( gm );
|
|
|
|
if( magic == '1' || magic == '4' )
|
|
{
|
|
gm_read_error = "invalid pbm file";
|
|
}
|
|
else if( magic == '2' || magic == '5' )
|
|
{
|
|
gm_read_error = "invalid pgm file";
|
|
}
|
|
else
|
|
{
|
|
gm_read_error = "invalid ppm file";
|
|
}
|
|
|
|
return -2;
|
|
|
|
std_error:
|
|
gm_free( gm );
|
|
return -1;
|
|
}
|
|
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
/* read BMP format */
|
|
|
|
struct bmp_info_s
|
|
{
|
|
unsigned int FileSize;
|
|
unsigned int reserved;
|
|
unsigned int DataOffset;
|
|
unsigned int InfoSize;
|
|
unsigned int w; /* width */
|
|
unsigned int h; /* height */
|
|
unsigned int Planes;
|
|
unsigned int bits; /* bits per sample */
|
|
unsigned int comp; /* compression mode */
|
|
unsigned int ImageSize;
|
|
unsigned int XpixelsPerM;
|
|
unsigned int YpixelsPerM;
|
|
unsigned int ncolors; /* number of colors in palette */
|
|
unsigned int ColorsImportant;
|
|
unsigned int RedMask;
|
|
unsigned int GreenMask;
|
|
unsigned int BlueMask;
|
|
unsigned int AlphaMask;
|
|
unsigned int ctbits; /* sample size for color table */
|
|
int topdown; /* top-down mode? */
|
|
};
|
|
typedef struct bmp_info_s bmp_info_t;
|
|
|
|
/* auxiliary */
|
|
|
|
static int bmp_count = 0; /* counter for byte padding */
|
|
static int bmp_pos = 0; /* counter from start of BMP data */
|
|
|
|
/* read n-byte little-endian integer. Return 1 on EOF or error, else
|
|
* 0. Assume n<=4. */
|
|
static int bmp_readint( FILE* f, int n, unsigned int* p )
|
|
{
|
|
int i;
|
|
unsigned int sum = 0;
|
|
int b;
|
|
|
|
for( i = 0; i < n; i++ )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
sum += (unsigned) b << ( 8 * i );
|
|
}
|
|
|
|
bmp_count += n;
|
|
bmp_pos += n;
|
|
*p = sum;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* reset padding boundary */
|
|
static void bmp_pad_reset( void )
|
|
{
|
|
bmp_count = 0;
|
|
}
|
|
|
|
|
|
/* read padding bytes to 4-byte boundary. Return 1 on EOF or error,
|
|
* else 0. */
|
|
static int bmp_pad( FILE* f )
|
|
{
|
|
int c, i, b;
|
|
|
|
c = ( -bmp_count ) & 3;
|
|
|
|
for( i = 0; i < c; i++ )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
{
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
bmp_pos += c;
|
|
bmp_count = 0;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* forward to the new file position. Return 1 on EOF or error, else 0 */
|
|
static int bmp_forward( FILE* f, int pos )
|
|
{
|
|
int b;
|
|
|
|
while( bmp_pos < pos )
|
|
{
|
|
b = fgetc( f );
|
|
|
|
if( b == EOF )
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
bmp_pos++;
|
|
bmp_count++;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* safe colortable access */
|
|
#define COLTABLE( c ) ( ( c ) < bmpinfo.ncolors ? coltable[( c )] : 0 )
|
|
|
|
/* read BMP stream after magic number. Return values as for gm_read.
|
|
* We choose to be as permissive as possible, since there are many
|
|
* programs out there which produce BMP. For instance, ppmtobmp can
|
|
* produce codings with anywhere from 1-8 or 24 bits per sample,
|
|
* although most specifications only allow 1,4,8,24,32. We can also
|
|
* read both the old and new OS/2 BMP formats in addition to the
|
|
* Windows BMP format. */
|
|
static int gm_readbody_bmp( FILE* f, greymap_t** gmp )
|
|
{
|
|
bmp_info_t bmpinfo;
|
|
int* coltable;
|
|
unsigned int b, c;
|
|
unsigned int i, j;
|
|
greymap_t* gm;
|
|
unsigned int x, y;
|
|
int col[2];
|
|
unsigned int bitbuf;
|
|
unsigned int n;
|
|
unsigned int redshift, greenshift, blueshift;
|
|
int realheight; /* in case of incomplete file, keeps track of how
|
|
* many scan lines actually contain data */
|
|
|
|
gm_read_error = NULL;
|
|
gm = NULL;
|
|
coltable = NULL;
|
|
|
|
bmp_pos = 2; /* set file position */
|
|
|
|
/* file header (minus magic number) */
|
|
TRY( bmp_readint( f, 4, &bmpinfo.FileSize ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.reserved ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.DataOffset ) );
|
|
|
|
/* info header */
|
|
TRY( bmp_readint( f, 4, &bmpinfo.InfoSize ) );
|
|
|
|
if( bmpinfo.InfoSize == 40 || bmpinfo.InfoSize == 64 || bmpinfo.InfoSize == 108
|
|
|| bmpinfo.InfoSize == 124 )
|
|
{
|
|
/* Windows or new OS/2 format */
|
|
bmpinfo.ctbits = 32; /* sample size in color table */
|
|
TRY( bmp_readint( f, 4, &bmpinfo.w ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.h ) );
|
|
TRY( bmp_readint( f, 2, &bmpinfo.Planes ) );
|
|
TRY( bmp_readint( f, 2, &bmpinfo.bits ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.comp ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.ImageSize ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.XpixelsPerM ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.YpixelsPerM ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.ncolors ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.ColorsImportant ) );
|
|
|
|
if( bmpinfo.InfoSize >= 108 )
|
|
{
|
|
/* V4 and V5 bitmaps */
|
|
TRY( bmp_readint( f, 4, &bmpinfo.RedMask ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.GreenMask ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.BlueMask ) );
|
|
TRY( bmp_readint( f, 4, &bmpinfo.AlphaMask ) );
|
|
}
|
|
|
|
if( bmpinfo.w > 0x7fffffff )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
if( bmpinfo.h > 0x7fffffff )
|
|
{
|
|
bmpinfo.h = ( -bmpinfo.h ) & 0xffffffff;
|
|
bmpinfo.topdown = 1;
|
|
}
|
|
else
|
|
{
|
|
bmpinfo.topdown = 0;
|
|
}
|
|
|
|
if( bmpinfo.h > 0x7fffffff )
|
|
{
|
|
goto format_error;
|
|
}
|
|
}
|
|
else if( bmpinfo.InfoSize == 12 )
|
|
{
|
|
/* old OS/2 format */
|
|
bmpinfo.ctbits = 24; /* sample size in color table */
|
|
TRY( bmp_readint( f, 2, &bmpinfo.w ) );
|
|
TRY( bmp_readint( f, 2, &bmpinfo.h ) );
|
|
TRY( bmp_readint( f, 2, &bmpinfo.Planes ) );
|
|
TRY( bmp_readint( f, 2, &bmpinfo.bits ) );
|
|
bmpinfo.comp = 0;
|
|
bmpinfo.ncolors = 0;
|
|
bmpinfo.topdown = 0;
|
|
}
|
|
else
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
if( bmpinfo.comp == 3 && bmpinfo.InfoSize < 108 )
|
|
{
|
|
/* bitfield feature is only understood with V4 and V5 format */
|
|
goto format_error;
|
|
}
|
|
|
|
if( bmpinfo.comp > 3 || bmpinfo.bits > 32 )
|
|
{
|
|
goto format_error;
|
|
}
|
|
|
|
/* forward to color table (e.g., if bmpinfo.InfoSize == 64) */
|
|
TRY( bmp_forward( f, 14 + bmpinfo.InfoSize ) );
|
|
|
|
if( bmpinfo.Planes != 1 )
|
|
{
|
|
gm_read_error = "cannot handle bmp planes";
|
|
goto format_error; /* can't handle planes */
|
|
}
|
|
|
|
if( bmpinfo.ncolors == 0 && bmpinfo.bits <= 8 )
|
|
{
|
|
bmpinfo.ncolors = 1 << bmpinfo.bits;
|
|
}
|
|
|
|
/* color table, present only if bmpinfo.bits <= 8. */
|
|
if( bmpinfo.bits <= 8 )
|
|
{
|
|
coltable = (int*) calloc( bmpinfo.ncolors, sizeof( int ) );
|
|
|
|
if( !coltable )
|
|
{
|
|
goto std_error;
|
|
}
|
|
|
|
/* NOTE: since we are reading a greymap, we can immediately convert
|
|
* the color table entries to grey values. */
|
|
for( i = 0; i < bmpinfo.ncolors; i++ )
|
|
{
|
|
TRY( bmp_readint( f, bmpinfo.ctbits / 8, &c ) );
|
|
c = ( ( c >> 16 ) & 0xff ) + ( ( c >> 8 ) & 0xff ) + ( c & 0xff );
|
|
coltable[i] = c / 3;
|
|
}
|
|
}
|
|
|
|
/* forward to data */
|
|
if( bmpinfo.InfoSize != 12 )
|
|
{
|
|
/* not old OS/2 format */
|
|
TRY( bmp_forward( f, bmpinfo.DataOffset ) );
|
|
}
|
|
|
|
/* allocate greymap */
|
|
gm = gm_new( bmpinfo.w, bmpinfo.h );
|
|
|
|
if( !gm )
|
|
{
|
|
goto std_error;
|
|
}
|
|
|
|
realheight = 0;
|
|
|
|
switch( bmpinfo.bits + 0x100 * bmpinfo.comp )
|
|
{
|
|
default:
|
|
goto format_error; break;
|
|
|
|
case 0x001: /* monochrome palette */
|
|
|
|
/* raster data */
|
|
for( y = 0; y < bmpinfo.h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
bmp_pad_reset();
|
|
|
|
for( i = 0; 8 * i < bmpinfo.w; i++ )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
|
|
for( j = 0; j < 8; j++ )
|
|
{
|
|
GM_PUT( gm, i * 8 + j, y, b & ( 0x80 >> j ) ? COLTABLE( 1 ) : COLTABLE( 0 ) );
|
|
}
|
|
}
|
|
|
|
TRY( bmp_pad( f ) );
|
|
}
|
|
|
|
break;
|
|
|
|
case 0x002: /* 2-bit to 8-bit palettes */
|
|
case 0x003:
|
|
case 0x004:
|
|
case 0x005:
|
|
case 0x006:
|
|
case 0x007:
|
|
case 0x008:
|
|
|
|
for( y = 0; y < bmpinfo.h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
bmp_pad_reset();
|
|
bitbuf = 0; /* bit buffer: bits in buffer are high-aligned */
|
|
n = 0; /* number of bits currently in bitbuffer */
|
|
|
|
for( x = 0; x < bmpinfo.w; x++ )
|
|
{
|
|
if( n < bmpinfo.bits )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
bitbuf |= b << ( INTBITS - 8 - n );
|
|
n += 8;
|
|
}
|
|
|
|
b = bitbuf >> ( INTBITS - bmpinfo.bits );
|
|
bitbuf <<= bmpinfo.bits;
|
|
n -= bmpinfo.bits;
|
|
GM_UPUT( gm, x, y, COLTABLE( b ) );
|
|
}
|
|
|
|
TRY( bmp_pad( f ) );
|
|
}
|
|
|
|
break;
|
|
|
|
case 0x010: /* 16-bit encoding */
|
|
/* can't do this format because it is not well-documented and I
|
|
* don't have any samples */
|
|
gm_read_error = "cannot handle bmp 16-bit coding";
|
|
goto format_error;
|
|
break;
|
|
|
|
case 0x018: /* 24-bit encoding */
|
|
case 0x020: /* 32-bit encoding */
|
|
|
|
for( y = 0; y < bmpinfo.h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
bmp_pad_reset();
|
|
|
|
for( x = 0; x < bmpinfo.w; x++ )
|
|
{
|
|
TRY_EOF( bmp_readint( f, bmpinfo.bits / 8, &c ) );
|
|
c = ( ( c >> 16 ) & 0xff ) + ( ( c >> 8 ) & 0xff ) + ( c & 0xff );
|
|
GM_UPUT( gm, x, y, c / 3 );
|
|
}
|
|
|
|
TRY( bmp_pad( f ) );
|
|
}
|
|
|
|
break;
|
|
|
|
case 0x320: /* 32-bit encoding with bitfields */
|
|
redshift = lobit( bmpinfo.RedMask );
|
|
greenshift = lobit( bmpinfo.GreenMask );
|
|
blueshift = lobit( bmpinfo.BlueMask );
|
|
|
|
for( y = 0; y < bmpinfo.h; y++ )
|
|
{
|
|
realheight = y + 1;
|
|
bmp_pad_reset();
|
|
|
|
for( x = 0; x < bmpinfo.w; x++ )
|
|
{
|
|
TRY_EOF( bmp_readint( f, bmpinfo.bits / 8, &c ) );
|
|
c = ( ( c & bmpinfo.RedMask ) >> redshift )
|
|
+ ( ( c & bmpinfo.GreenMask ) >> greenshift )
|
|
+ ( ( c & bmpinfo.BlueMask ) >> blueshift );
|
|
GM_UPUT( gm, x, y, c / 3 );
|
|
}
|
|
|
|
TRY( bmp_pad( f ) );
|
|
}
|
|
|
|
break;
|
|
|
|
case 0x204: /* 4-bit runlength compressed encoding (RLE4) */
|
|
x = 0;
|
|
y = 0;
|
|
|
|
while( 1 )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) ); /* opcode */
|
|
TRY_EOF( bmp_readint( f, 1, &c ) ); /* argument */
|
|
|
|
if( b > 0 )
|
|
{
|
|
/* repeat count */
|
|
col[0] = COLTABLE( ( c >> 4 ) & 0xf );
|
|
col[1] = COLTABLE( c & 0xf );
|
|
|
|
for( i = 0; i < b && x < bmpinfo.w; i++ )
|
|
{
|
|
if( x >= bmpinfo.w )
|
|
{
|
|
x = 0;
|
|
y++;
|
|
}
|
|
|
|
if( x >= bmpinfo.w || y >= bmpinfo.h )
|
|
{
|
|
break;
|
|
}
|
|
|
|
realheight = y + 1;
|
|
GM_PUT( gm, x, y, col[i & 1] );
|
|
x++;
|
|
}
|
|
}
|
|
else if( c == 0 )
|
|
{
|
|
/* end of line */
|
|
y++;
|
|
x = 0;
|
|
}
|
|
else if( c == 1 )
|
|
{
|
|
/* end of greymap */
|
|
break;
|
|
}
|
|
else if( c == 2 )
|
|
{
|
|
/* "delta": skip pixels in x and y directions */
|
|
TRY_EOF( bmp_readint( f, 1, &b ) ); /* x offset */
|
|
TRY_EOF( bmp_readint( f, 1, &c ) ); /* y offset */
|
|
x += b;
|
|
y += c;
|
|
}
|
|
else
|
|
{
|
|
/* verbatim segment */
|
|
for( i = 0; i < c; i++ )
|
|
{
|
|
if( ( i & 1 ) == 0 )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
}
|
|
|
|
if( x >= bmpinfo.w )
|
|
{
|
|
x = 0;
|
|
y++;
|
|
}
|
|
|
|
if( x >= bmpinfo.w || y >= bmpinfo.h )
|
|
{
|
|
break;
|
|
}
|
|
|
|
realheight = y + 1;
|
|
GM_PUT( gm, x, y, COLTABLE( ( b >> ( 4 - 4 * ( i & 1 ) ) ) & 0xf ) );
|
|
x++;
|
|
}
|
|
|
|
if( ( c + 1 ) & 2 )
|
|
{
|
|
/* pad to 16-bit boundary */
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
}
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case 0x108: /* 8-bit runlength compressed encoding (RLE8) */
|
|
x = 0;
|
|
y = 0;
|
|
|
|
while( 1 )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) ); /* opcode */
|
|
TRY_EOF( bmp_readint( f, 1, &c ) ); /* argument */
|
|
|
|
if( b > 0 )
|
|
{
|
|
/* repeat count */
|
|
for( i = 0; i < b; i++ )
|
|
{
|
|
if( x >= bmpinfo.w )
|
|
{
|
|
x = 0;
|
|
y++;
|
|
}
|
|
|
|
if( x >= bmpinfo.w || y >= bmpinfo.h )
|
|
{
|
|
break;
|
|
}
|
|
|
|
realheight = y + 1;
|
|
GM_PUT( gm, x, y, COLTABLE( c ) );
|
|
x++;
|
|
}
|
|
}
|
|
else if( c == 0 )
|
|
{
|
|
/* end of line */
|
|
y++;
|
|
x = 0;
|
|
}
|
|
else if( c == 1 )
|
|
{
|
|
/* end of greymap */
|
|
break;
|
|
}
|
|
else if( c == 2 )
|
|
{
|
|
/* "delta": skip pixels in x and y directions */
|
|
TRY_EOF( bmp_readint( f, 1, &b ) ); /* x offset */
|
|
TRY_EOF( bmp_readint( f, 1, &c ) ); /* y offset */
|
|
x += b;
|
|
y += c;
|
|
}
|
|
else
|
|
{
|
|
/* verbatim segment */
|
|
for( i = 0; i < c; i++ )
|
|
{
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
|
|
if( x >= bmpinfo.w )
|
|
{
|
|
x = 0;
|
|
y++;
|
|
}
|
|
|
|
if( x >= bmpinfo.w || y >= bmpinfo.h )
|
|
{
|
|
break;
|
|
}
|
|
|
|
realheight = y + 1;
|
|
GM_PUT( gm, x, y, COLTABLE( b ) );
|
|
x++;
|
|
}
|
|
|
|
if( c & 1 )
|
|
{
|
|
/* pad input to 16-bit boundary */
|
|
TRY_EOF( bmp_readint( f, 1, &b ) );
|
|
}
|
|
}
|
|
}
|
|
|
|
break;
|
|
} /* switch */
|
|
|
|
/* skip any potential junk after the data section, but don't
|
|
* complain in case EOF is encountered */
|
|
bmp_forward( f, bmpinfo.FileSize );
|
|
|
|
free( coltable );
|
|
|
|
if( bmpinfo.topdown )
|
|
{
|
|
gm_flip( gm );
|
|
}
|
|
|
|
*gmp = gm;
|
|
return 0;
|
|
|
|
eof:
|
|
TRY_STD( gm_resize( gm, realheight ) );
|
|
free( coltable );
|
|
|
|
if( bmpinfo.topdown )
|
|
{
|
|
gm_flip( gm );
|
|
}
|
|
|
|
*gmp = gm;
|
|
return 1;
|
|
|
|
format_error:
|
|
try_error:
|
|
free( coltable );
|
|
gm_free( gm );
|
|
|
|
if( !gm_read_error )
|
|
{
|
|
gm_read_error = "invalid bmp file";
|
|
}
|
|
|
|
return -2;
|
|
|
|
std_error:
|
|
free( coltable );
|
|
gm_free( gm );
|
|
return -1;
|
|
}
|
|
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
|
|
/* write a pgm stream, either P2 or (if raw != 0) P5 format. Include
|
|
* one-line comment if non-NULL. Mode determines how out-of-range
|
|
* color values are converted. Gamma is the desired gamma correction,
|
|
* if any (set to 2.2 if the image is to look optimal on a CRT monitor,
|
|
* 2.8 for LCD). Set to 1.0 for no gamma correction */
|
|
|
|
int gm_writepgm( FILE* f, greymap_t* gm, const char* comment, int raw, int mode, double gamma )
|
|
{
|
|
int x, y, v;
|
|
int gammatable[256];
|
|
|
|
/* prepare gamma correction lookup table */
|
|
if( gamma != 1.0 )
|
|
{
|
|
gammatable[0] = 0;
|
|
|
|
for( v = 1; v < 256; v++ )
|
|
{
|
|
gammatable[v] = (int) ( 255 * exp( log( v / 255.0 ) / gamma ) + 0.5 );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for( v = 0; v < 256; v++ )
|
|
{
|
|
gammatable[v] = v;
|
|
}
|
|
}
|
|
|
|
fprintf( f, raw ? "P5\n" : "P2\n" );
|
|
|
|
if( comment && *comment )
|
|
{
|
|
fprintf( f, "# %s\n", comment );
|
|
}
|
|
|
|
fprintf( f, "%d %d 255\n", gm->w, gm->h );
|
|
|
|
for( y = gm->h - 1; y >= 0; y-- )
|
|
{
|
|
for( x = 0; x < gm->w; x++ )
|
|
{
|
|
v = GM_UGET( gm, x, y );
|
|
|
|
if( mode == GM_MODE_NONZERO )
|
|
{
|
|
if( v > 255 )
|
|
{
|
|
v = 510 - v;
|
|
}
|
|
|
|
if( v < 0 )
|
|
{
|
|
v = 0;
|
|
}
|
|
}
|
|
else if( mode == GM_MODE_ODD )
|
|
{
|
|
v = mod( v, 510 );
|
|
|
|
if( v > 255 )
|
|
{
|
|
v = 510 - v;
|
|
}
|
|
}
|
|
else if( mode == GM_MODE_POSITIVE )
|
|
{
|
|
if( v < 0 )
|
|
{
|
|
v = 0;
|
|
}
|
|
else if( v > 255 )
|
|
{
|
|
v = 255;
|
|
}
|
|
}
|
|
else if( mode == GM_MODE_NEGATIVE )
|
|
{
|
|
v = 510 - v;
|
|
|
|
if( v < 0 )
|
|
{
|
|
v = 0;
|
|
}
|
|
else if( v > 255 )
|
|
{
|
|
v = 255;
|
|
}
|
|
}
|
|
|
|
v = gammatable[v];
|
|
|
|
if( raw )
|
|
{
|
|
fputc( v, f );
|
|
}
|
|
else
|
|
{
|
|
fprintf( f, x == gm->w - 1 ? "%d\n" : "%d ", v );
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
/* output - for primitive debugging purposes only! */
|
|
|
|
/* print greymap to screen */
|
|
int gm_print( FILE* f, greymap_t* gm )
|
|
{
|
|
int x, y;
|
|
int xx, yy;
|
|
int d, t;
|
|
int sw, sh;
|
|
|
|
sw = gm->w < 79 ? gm->w : 79;
|
|
sh = gm->w < 79 ? gm->h : gm->h * sw * 44 / ( 79 * gm->w );
|
|
|
|
for( yy = sh - 1; yy >= 0; yy-- )
|
|
{
|
|
for( xx = 0; xx < sw; xx++ )
|
|
{
|
|
d = 0;
|
|
t = 0;
|
|
|
|
for( x = xx * gm->w / sw; x < ( xx + 1 ) * gm->w / sw; x++ )
|
|
{
|
|
for( y = yy * gm->h / sh; y < ( yy + 1 ) * gm->h / sh; y++ )
|
|
{
|
|
d += GM_GET( gm, x, y );
|
|
t += 256;
|
|
}
|
|
}
|
|
|
|
fputc( "*#=- "[5 * d / t], f ); /* what a cute trick :) */
|
|
}
|
|
|
|
fputc( '\n', f );
|
|
}
|
|
|
|
return 0;
|
|
}
|